HV20 Aperture Control at DVinfo.net

Jeff Alldridge · March 1st, 2007, 06:54 PM

I hope this hasn't been addressed already, but does anyone know any details on the HV20's aperture control?

The manual says:
Set the aperture value. The camcorder automatically sets the appropriate shutter speed. Use low aperture values (larger lens opening) to softly blur the background in a portrait or high aperture values (smaller lens opening) to get a wider depth of field, giving a sharp focus all throughout a landscape.

Since this camera borrows many aspects from Canon's still cameras, I wonder how this camcorder aperture works in video.

My assumption is the "exposure" is essentially the ISO change. So there's exposure, shutter speed, and aperture that can all make a difference.

I guess what I am getting to is, I wonder how much you could control the depth of field with the camera's aperture.

I don't know if this would replace the use of a 35mm adapter. The effect would still be different, but that opens up JUST as much opportunity to control depth-of-field as hearing there was a cheap 24p 1080 HDV camera.

Any thoughts?

Rich Dykmans · March 1st, 2007, 08:52 PM

Quote:

Originally Posted by Jeff Alldridge

My assumption is the "exposure" is essentially the ISO change.

I believe the exposure dial controls the aperture while in TV mode and the shutter while in AV mode. The problem is you don't know exactly what speed or opening the exposure dial is actually giving you (plus either the ND's or gain may both kick in given the starting exposure level). If you research the threads on this forum there have been some tips as to how HV10 should react when using manually controls.

That being said I've had decent results shooting in TV mode, using the exposure dial and the zebras.

Pieter Jongerius · March 2nd, 2007, 02:11 PM

Hi Jeff,

additionally: ISO setting on Canon's still cams (and I guess on other brands also) is pure gain: multiplying the sampled signal to artificially lighten up the picture. As Rich points out, 'exposure' (in camcorders as well as in still cams) is a mix of things.

Second: although max aperture indeed gives you minimal DOF, it will be nowhere near the dramatic effect of a 35mm adaptor. For my home use though, it is sufficient. Plus, remember that for DOF recordings, such as portraits, it also helps to use max zoom.

Pieter

Bill Busby · March 4th, 2007, 12:53 AM

Quote:

Originally Posted by Rich Dykmans

I believe the exposure dial controls the aperture while in TV mode and the shutter while in AV mode.

That being said I've had decent results shooting in TV mode, using the exposure dial and the zebras.

It's actually the other way around. TV (Time Value) mode is Shutter Priority & the AV (Aperture Value) mode is the Aperture Priority.

Bill

Ron Lemming · March 4th, 2007, 06:21 AM

Wasn't that what he said? While in Tv mode, the only way to control aparture is with the exposure dial. And the only way to control the shutter in Av mode is by using the same dial. If you didn't, the aparture would be on auto when in Tv mode and the shutter would be on auto when in Av mode.

Rich Dykmans · March 4th, 2007, 09:18 AM

Quote:

Originally Posted by Bill Busby

It's actually the other way around. TV (Time Value) mode is Shutter Priority & the AV (Aperture Value) mode is the Aperture Priority.

Bill

No it isn't, shutter is locked in TV mode and exposure dial controls aperture.

Aperture is locked in AV mode and exposure dial controls shutter.

What I'm not sure anyone has figured out is exactly when gain kicks in in low light situations and where the ND's engage on the other end.

Ron Lemming · March 4th, 2007, 11:23 AM

What are you arguing about? You are both right. :)
Shutter Priority (Tv) means that the shutter is locked and the aparture is on auto.
Aparture Priority (Av) means that the aparture is locked and the shutter is on auto.
The dial can be used to lock the aparture in Shutter Priority (Tv) mode or to lock the shutter speed in Aparture Priority (Av) mode.

Has any HV10 owner out there done some tests to determine where the gain kicks in? I suppose it would be the same on the HV20.

Bill Busby · March 4th, 2007, 12:45 PM

I'm crackin' up! I wasn't arguing. It was late & I was tired, & I'm not going to attempt to go back & re-read again because I just woke up a bit ago :D

Bill

Yow Siang · March 4th, 2007, 06:58 PM

great to know there are Av and Tv mode however my problem with some cameras are despite the fact in Av or Tv mode the camera will still have the Gain on auto. My worry is even in Av or Tv mode under dark conditions will the HV20 increase the gain say +18db automatically? or i can actually have the Gain on Manual too?

ys

Rich Dykmans · March 4th, 2007, 09:47 PM

There was a thread earlier in this forum where someone posted the settings for an Optura, when the gain started etc and how to set initial exposure lock and then avoid gain. The thought was the same might work for the HV10. Hopefully someone will figure it out.

Ron Lemming · March 5th, 2007, 01:39 AM

But I wonder, is it even safe to say that the EXP dial controls the aparture in Tv mode or shutter in Av mode? How do we know it just doesn't add or subtract gain when you use that dial?

How does that work on the HV10? You should be able to tell by setting the camera in Tv mode, zooming in all the way, keeping the background out of focus and then see if the background gets sharper when you dial the EXP dial down (or more blurry when you dial it up). If it does that it means it adjusts the aparture and it's all good.
Or you could set the camera in Av mode and do a pan while you dial the EXP dial up and down. If the motion looks more stroby when you dial it up (or down, I don't know) then it means it adjusts the shutter speed and it's all good.

Mathieu Kassovitz · March 10th, 2007, 03:32 AM

http://www.dvinfo.net/conf/showthrea...330#post622330

Toenis Liivamaegi · March 22nd, 2007, 07:01 AM

Can I set aperture and shutter speed manually at the same time on HV20?
I keep reading about TV and the (almost pointless) AV mode but does the the HV20 have a real manual exposure control also known as "M" the manual mode.
If not it will not be as usable with DOF adaptors as many would think.

Thanks in advance,
T

Chris Hurd · March 22nd, 2007, 08:17 AM

Quote:

Originally Posted by Toenis Liivamaegi

Can I set aperture and shutter speed manually at the same time on HV20?

Toenis, the post directly above yours, from Mathieu Kassovitz, has a link to a thread which answers your question in detail. The short answer is yes. The longer answer is in that thread. Hope this helps,

March 1st, 2007, 06:54 PM	#1
Jeff Alldridge New Boot Join Date: Feb 2007 Location: Redmond, WA Posts: 6	HV20 Aperture Control I hope this hasn't been addressed already, but does anyone know any details on the HV20's aperture control? The manual says: Set the aperture value. The camcorder automatically sets the appropriate shutter speed. Use low aperture values (larger lens opening) to softly blur the background in a portrait or high aperture values (smaller lens opening) to get a wider depth of field, giving a sharp focus all throughout a landscape. Since this camera borrows many aspects from Canon's still cameras, I wonder how this camcorder aperture works in video. My assumption is the "exposure" is essentially the ISO change. So there's exposure, shutter speed, and aperture that can all make a difference. I guess what I am getting to is, I wonder how much you could control the depth of field with the camera's aperture. I don't know if this would replace the use of a 35mm adapter. The effect would still be different, but that opens up JUST as much opportunity to control depth-of-field as hearing there was a cheap 24p 1080 HDV camera. Any thoughts?

March 4th, 2007, 06:58 PM	#9
Yow Siang Regular Crew Join Date: Jan 2003 Location: Singapore Posts: 153	is Gain auto on Av/Tv mode? great to know there are Av and Tv mode however my problem with some cameras are despite the fact in Av or Tv mode the camera will still have the Gain on auto. My worry is even in Av or Tv mode under dark conditions will the HV20 increase the gain say +18db automatically? or i can actually have the Gain on Manual too? ys

March 22nd, 2007, 07:01 AM	#13
Toenis Liivamaegi Major Player Join Date: Nov 2005 Location: Tartu, Estonia Posts: 579	Does the the HV20 have a real manual exposure control? Can I set aperture and shutter speed manually at the same time on HV20? I keep reading about TV and the (almost pointless) AV mode but does the the HV20 have a real manual exposure control also known as "M" the manual mode. If not it will not be as usable with DOF adaptors as many would think. Thanks in advance, T

March 2nd, 2007, 02:11 PM	#3
Pieter Jongerius Regular Crew Join Date: Jan 2007 Location: Netherlands Posts: 101	Hi Jeff, additionally: ISO setting on Canon's still cams (and I guess on other brands also) is pure gain: multiplying the sampled signal to artificially lighten up the picture. As Rich points out, 'exposure' (in camcorders as well as in still cams) is a mix of things. Second: although max aperture indeed gives you minimal DOF, it will be nowhere near the dramatic effect of a 35mm adaptor. For my home use though, it is sufficient. Plus, remember that for DOF recordings, such as portraits, it also helps to use max zoom. Pieter

March 4th, 2007, 06:21 AM	#5
Ron Lemming Regular Crew Join Date: Oct 2006 Location: Sweden Posts: 46	Wasn't that what he said? While in Tv mode, the only way to control aparture is with the exposure dial. And the only way to control the shutter in Av mode is by using the same dial. If you didn't, the aparture would be on auto when in Tv mode and the shutter would be on auto when in Av mode.

March 4th, 2007, 11:23 AM	#7
Ron Lemming Regular Crew Join Date: Oct 2006 Location: Sweden Posts: 46	What are you arguing about? You are both right. :) Shutter Priority (Tv) means that the shutter is locked and the aparture is on auto. Aparture Priority (Av) means that the aparture is locked and the shutter is on auto. The dial can be used to lock the aparture in Shutter Priority (Tv) mode or to lock the shutter speed in Aparture Priority (Av) mode. Has any HV10 owner out there done some tests to determine where the gain kicks in? I suppose it would be the same on the HV20.

March 4th, 2007, 12:45 PM	#8
Bill Busby Major Player Join Date: Dec 2006 Location: Los Angeles, CA Posts: 959	I'm crackin' up! I wasn't arguing. It was late & I was tired, & I'm not going to attempt to go back & re-read again because I just woke up a bit ago :D Bill

March 4th, 2007, 09:47 PM	#10
Rich Dykmans Regular Crew Join Date: Dec 2006 Location: Discovery Bay, CA Posts: 138	There was a thread earlier in this forum where someone posted the settings for an Optura, when the gain started etc and how to set initial exposure lock and then avoid gain. The thought was the same might work for the HV10. Hopefully someone will figure it out.

March 5th, 2007, 01:39 AM	#11
Ron Lemming Regular Crew Join Date: Oct 2006 Location: Sweden Posts: 46	But I wonder, is it even safe to say that the EXP dial controls the aparture in Tv mode or shutter in Av mode? How do we know it just doesn't add or subtract gain when you use that dial? How does that work on the HV10? You should be able to tell by setting the camera in Tv mode, zooming in all the way, keeping the background out of focus and then see if the background gets sharper when you dial the EXP dial down (or more blurry when you dial it up). If it does that it means it adjusts the aparture and it's all good. Or you could set the camera in Av mode and do a pan while you dial the EXP dial up and down. If the motion looks more stroby when you dial it up (or down, I don't know) then it means it adjusts the shutter speed and it's all good.

March 10th, 2007, 03:32 AM	#12
Mathieu Kassovitz Major Player Join Date: Apr 2006 Location: paris Posts: 289	http://www.dvinfo.net/conf/showthrea...330#post622330